Which specific vertebral surfaces determine how one vertebra articulates with the next in the spine?
Answer
The pre- and post-zygapophyses
Phylogenetic analysis often hinges on minute details of vertebral connection, especially in fragmented specimens where overall shape is unclear. The surfaces responsible for linking adjacent vertebrae in the spinal column are known as the pre-zygapophyses (anterior articulating surfaces) and the post-zygapophyses (posterior articulating surfaces). The specific orientation, angle, and connection patterns of these zygapophyses relative to the neural arch elements provide critical diagnostic information that can swing a cladistic analysis toward placing *Xenoposeidon* closer to the morphology seen in *Brachiosaurus* or more derived titanosaurs.
Related Questions
What Greek roots combine to form the genus name *Xenoposeidon*?What specific anatomical structure does the specific epithet *pronelkocamerus* reference?To which Order do both *Xenoposeidon* and *Diplodocus* belong based on their general classification?What specific term denotes the large, deep pneumatic hollows observed in *Xenoposeidon*'s vertebrae?Approximately how tall was the primary dorsal vertebra used to describe *Xenoposeidon*?What Latin term describes the temporary classification given when a genus lacks sufficient evidence for firm placement?What characteristic of the type specimen contributes most to the phylogenetic ambiguity of *Xenoposeidon*?Which infraorder clade is suggested to group titanosaurs and brachiosaurids, potentially linking *Xenoposeidon*?What modern digital technique is employed to overcome taphonomic distortion when analyzing *Xenoposeidon*'s fragile vertebrae?Which specific vertebral surfaces determine how one vertebra articulates with the next in the spine?